1. Field of the Invention
The present invention relates to a grommet assembly for protecting main and auxiliary wire harnesses against damage which is possible when the wire harnesses are put through a panel of an automotive vehicle so as to be connected to electric components equipped on the automotive vehicle, as well as for preventing water and noise from entering the passenger compartment from the engine compartment of the automotive vehicle.
2. Prior Art
The wire harness-holding portion of a conventional grommet of the type adapted to function to prevent water and noise from entering the inside of the passenger compartment of an automotive vehicle is constituted by a small diameter tubular portion. The Japanese Utility Model Lain-Open No. 134824/1983 discloses a grommet adapted to be used when a plurality of wire harnesses are put through a panel of the passenger compartment. This grommet was contrived in order to meet the current growing tendency in the automotive industries that more and more electric parts such as cassette players or the like are equipped on automotive vehicles as optional equipment in the wake of the development of electronics in the automotive industries. In this grommet, in addition to a portion through which a main wire harness is put, a portion through which an auxiliary wire harness for an optional electric part is put is also formed.
To be specific, the grommet disclosed in the above Japanese document is intended to be used at a certain process of the production line to fix together a general purpose main wire harness and an auxiliary wire harness for an optional electric part, which are separately produced.
FIGS. 4 and 5 show a conventional grommet 2' that is fitted in a fixing hole formed in a panel 1 in the direction from the engine compartment side toward the passenger compartment side. In this conventional grommet 2', alongside of a portion 4' through which a main wire harness 3 is put before the shipment from a factory, at least one portion 4a is provided through which an auxiliary wire harness for an optional electric part can pass. This auxiliary wire harness putting-through portion 4a is formed into a conical hollow projection so as to provide the proper sealing efficiency. When an auxiliary wire harness 6 (FIG. 5) for an optional electric part is put through this portion of the grommet 2', the conical hollow projection is cut at a desired position A in such a manner as to produce a small diameter tubular portion 14a the inside diameter of which coincides with the oustide diameter of the auxiliary wire harness 6, whereby water and noise are prevented from entering the passenger compartment of an automotive vehicle.
However, with this conventional grommet, the main wire harness 3 is first put through the main wire harness putting-through portion 4' thereof, and the grommet 2' is then fitted in a fixing hole provided in a panel. Afterwards, the auxiliary wire harness putting-through portion 4a is cut at a desired position along the length thereof so as to produce the small diameter tubular portion 14a, which is then press expanded so as to allow the auxiliary wire harness 6 to be put therethrough.
As is clear from the above, a special tool is needed to expand the small diameter tubular portion 14a of the auxiliary wire harness putting-through portion 4a in order to allow the auxiliary wire harness 6 (FIG. 5) to be put therethrough after the grommet in which only the main wire harness 3 extending through the main wire harness putting-through portion 4' has been fitted in a hole provided in the panel of an automotive vehicle. This is very difficult to be achieved due to the limited space of the engine compartment of an automotive vehicle.